qwt_graphic.h

/******************************************************************************
 * Qwt Widget Library
 * Copyright (C) 1997   Josef Wilgen
 * Copyright (C) 2002   Uwe Rathmann
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the Qwt License, Version 1.0
 *
 * Modified by ChenZongYan in 2024 <czy.t@163.com>
 *   Summary of major modifications (see ChangeLog.md for full history):
 *   1. CMake build system & C++11 throughout.
 *   2. Core panner/ zoomer refactored:
 *        - QwtPanner → QwtCachePanner (pixmap-cache version)
 *        - New real-time QwtPlotPanner derived from QwtPicker.
 *   3. Zoomer supports multi-axis.
 *   4. Parasite-plot framework:
 *        - QwtFigure, QwtPlotParasiteLayout, QwtPlotTransparentCanvas,
 *        - QwtPlotScaleEventDispatcher, built-in pan/zoom on axis.
 *   5. New picker: QwtPlotSeriesDataPicker (works with date axis).
 *   6. Raster & color-map extensions:
 *        - QwtGridRasterData (2-D table + interpolation)
 *        - QwtLinearColorMap::stopColors(), stopPos() API rename.
 *   7. Bar-chart: expose pen/brush control.
 *   8. Amalgamated build: single QwtPlot.h / QwtPlot.cpp pair in src-amalgamate.
 *****************************************************************************/
 
#ifndef QWT_GRAPHIC_H
#define QWT_GRAPHIC_H
 
#include "qwt_global.h"
#include "qwt_null_paintdevice.h"
#include "qwt_painter_command.h"
 
#include <qmetatype.h>
 
class QWT_EXPORT QwtGraphic : public QwtNullPaintDevice
{
  public:
    enum RenderHint
    {
        RenderPensUnscaled = 0x1
    };
 
    Q_DECLARE_FLAGS( RenderHints, RenderHint )
 
    
    enum CommandType
    {
        VectorData     = 1 << 0,
 
        RasterData     = 1 << 1,
 
        Transformation = 1 << 2
    };
 
    Q_DECLARE_FLAGS( CommandTypes, CommandType )
 
    // Constructor
    QwtGraphic();
    // Copy constructor
    QwtGraphic( const QwtGraphic& );
 
    // Destructor
    virtual ~QwtGraphic();
 
    // Assignment operator
    QwtGraphic& operator=( const QwtGraphic& );
 
    // Clear all stored commands
    void reset();
 
    // Check if the graphic is null
    bool isNull() const;
    // Check if the graphic is empty
    bool isEmpty() const;
 
    // Get the types of painter commands being used
    CommandTypes commandTypes() const;
 
    // Replay all recorded painter commands
    void render( QPainter* ) const;
 
    // Render graphic scaled to fit into given size
    void render( QPainter*, const QSizeF&,
        Qt::AspectRatioMode = Qt::IgnoreAspectRatio ) const;
 
    // Render graphic aligned to a position
    void render( QPainter*, const QPointF&,
        Qt::Alignment = Qt::AlignTop | Qt::AlignLeft ) const;
 
    // Render graphic scaled to fit into given rectangle
    void render( QPainter*, const QRectF&,
        Qt::AspectRatioMode = Qt::IgnoreAspectRatio ) const;
 
    // Convert graphic to QPixmap in default size
    QPixmap toPixmap( qreal devicePixelRatio = 0.0 ) const;
 
    // Convert graphic to QPixmap with specified size
    QPixmap toPixmap( const QSize&,
        Qt::AspectRatioMode = Qt::IgnoreAspectRatio,
        qreal devicePixelRatio = 0.0 ) const;
 
    // Convert graphic to QImage in default size
    QImage toImage( qreal devicePixelRatio = 0.0 ) const;
 
    // Convert graphic to QImage with specified size
    QImage toImage( const QSize&,
        Qt::AspectRatioMode = Qt::IgnoreAspectRatio,
        qreal devicePixelRatio = 0.0 ) const;
 
    // Calculate the scaled bounding rectangle
    QRectF scaledBoundingRect( qreal sx, qreal sy ) const;
 
    // Get the bounding rectangle
    QRectF boundingRect() const;
    // Get the control point rectangle
    QRectF controlPointRect() const;
 
    // Get the list of recorded paint commands
    const QVector< QwtPainterCommand >& commands() const;
    // Set the paint commands
    void setCommands( const QVector< QwtPainterCommand >& );
 
    // Set the default size
    void setDefaultSize( const QSizeF& );
    // Get the default size
    QSizeF defaultSize() const;
 
    // Get the height for a given width
    qreal heightForWidth( qreal width ) const;
    // Get the width for a given height
    qreal widthForHeight( qreal height ) const;
 
    // Set a render hint
    void setRenderHint( RenderHint, bool on = true );
    // Test a render hint
    bool testRenderHint( RenderHint ) const;
 
    // Get the render hints
    RenderHints renderHints() const;
 
  protected:
    virtual QSize sizeMetrics() const override;
 
    virtual void drawPath( const QPainterPath& ) override;
 
    virtual void drawPixmap( const QRectF&,
        const QPixmap&, const QRectF& ) override;
 
    virtual void drawImage( const QRectF&, const QImage&,
        const QRectF&, Qt::ImageConversionFlags ) override;
 
    virtual void updateState( const QPaintEngineState& ) override;
 
  private:
    void renderGraphic( QPainter*, QTransform* ) const;
 
    void updateBoundingRect( const QRectF& );
    void updateControlPointRect( const QRectF& );
 
    class PathInfo;
 
    class PrivateData;
    PrivateData* m_data;
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS( QwtGraphic::RenderHints )
Q_DECLARE_OPERATORS_FOR_FLAGS( QwtGraphic::CommandTypes )
Q_DECLARE_METATYPE( QwtGraphic )
 
#endif